Combustion system



Jam... 9, 1923, 1,4411,

L. L. SCOTT ET AL.

COMBUSTION SYSTEM.

FI LED FEB- 8, 1919.

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LEWIS SCOTT AND ALLEN C. S'IAIJLEY, OI ST. LOUIS, MISSOURI, ASSIGNOS TO STANDARD ENGINEERING COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION.

COMBUSTION SYSTEM.

Application filed February 8, 1919. Serial No. 2753M.

To all whom it may concern 7 Be it known that we, LEWIS L. Soo'r'r and ALIEN C. STALEY, citizens of the United States, residing in the city .of St. Louis and State of Missouri, have invented new and useful Improvements in Combustion Systems, of which the following is a specification.

This invention relates to certain new and useful improvements in combustion systems,

and particularly of the type disclosed inapplication of Lewis L. Scott, Serial No.

241,590, filed June 24., 1918. v p

- One of the objects of the invention is to provide a fuel feed regulating device, whereby to prevent the kerosenegor other oil, fed

to the spray nozzle, from dripping or.

running through the nozzle on starting the system in operation and before-the pressure has built up sufficiently to cause the fuel oil to spray.

Another object of the invention is to initially retard the production of ignition relative to the supply of air, and preferably by providing means for retarding the spraying of the fuel oil until the air supplied to complete combustion of the fuel has had time to enter the combustion chamber and drive out spent gases remaining from a prior operation, so that the ignition of the oil may occur immediately upon the spray starting.

A final object of the invention is to provide automatically operating means, shown, in the present embodiment of the invention, in the form of a checkvalve located in the air duct through which air passes to the combustion chamber, to prevent heat and products "of combustion from passing back into the fan casing and thence to the outer air when the operation of the fan is stopped. v

In the drawing, the figure is a view partly in section and partly in elevation of so muc of the Scott system as is necessary to illustrate the location and operation of our improvement.

Referring to the drawing, the numeral 1 indicates a steam generator. of the type shown in the application referred to, which is inclosed in a casing 2 having an air.

chamber 3 provided on its top and con municating with an an duct 4. In the top of the air chamber is located a primary combustion chamber 5 which is surrounded mbunted in said housing.

pry a spout 6 leadin from the air chamber. he numeral 7 in lcates the spray nozzle for spraying fuel into the chamber 5, and the numeral 8 the spark plug for i iting the sprayed fuel. connected to and communicates with a valve casing 9 in which is seated a valve 10 the stem 11 of which is guided in a housing 12 and works against a spring 13 the spring 13 is adjusted to hold the valve 10 to its seat under a 'ven pressure, which, in the system. referre 10 lbs. The numeral 14 indicates the 'fuel oil supply pipe which communicates with the casing 9 below the valve 10. The valve 10 governs a port aflording communication between the pipe ltand spray nozzle 7, and by its spring 13 controls the pressure at whlch the fuel oilshall pass to the spray nozzle. 7

Located at any suitable point in the length of thepipe 14 is a pressure chamber 15, which communicates with said'pipe. The

purpose ofthis' chamber will be presently described. The numeral 16 indicates the fuel oil tank which communicates by a pipe 17 with a pump 18 driven from a motor 19,.and a pipe 20 leads from the pump to thepipe 14, the latter communicating with a by-pass 21 from which a pipe 22 leads tothe suction side of the pump. The by-pass is controlled by a solenoid valve 23. The numeral -24: indicates the water 26, also operated by the motor 19. A pipe 27 leads from the pump 26 to the steam generator 1. The electrical and other connections are indicated diagrammatically, but not described, as they form, as such, no part of the present invention.

Referring now to the pressure chamber it .will be'clear that with the pump'18 in operationforcing the fuel oil through the -p1pe 1 1, the said chamber must first be supplied with the oil and the pressure there- 'of against the air trapped ill said chamber built up before the pressure of the oil can eflect a lifting mbvement of the valve 10. I

This will necessarily delay the'periodwhen the oil will be sprayed from the nozzle 7,

and during this interval the ,air passing into the combustion chamberthrough the duct 4: will carry away the spent gases that may have remained from a prior operation,

The spray nozz e7 is 60 The pressure of 65 to, would be about tank from which a pipe 25" leads to a pump to I insuring, when the oil is finally sprayed, an atmosphere of pure air for the initial and complete combustion of thefuel. By adjusting the size of the chamber 15, the retardation of the spray of the oil maybe varied in degree as may be found desirable.

When the pressure of 'the fuel oil in pipe 14: and chamber 15 has been built up to, say, 10 lbs, the valve 10 will be lifted rom its seat and the oil under pressure pass to the spray nozzle 7, thus insuring that any oil escaping from said nozzle will be in'the form of a spray. As soon as thepump 18 stops, and the pressure in the pipe 14 falls below 10 lbs., the valve 10 will be forced to its seat bv the spring 13, thus preventing the passage of further oil to the spray nozzle, and its escape therefrom in drops, or a small stream, in which condition it is practically non-ignitable by the elec tric spark.

The final feature of our invention resides in the provision of suitable means to prevent back-fiow of products of combustion into the fan casing. This casing is indicatediat 28 and is connected to the air duct 4. To illustrate one way of accomplishing the above object, we show locate-d, at any suitable point in the air duct, a flap-valve 29 hinged at one side to the side of the air duct, as shown at 30 and resting upon a seat 31. This valve is quite light and readily opens outwardly, or, in the case shown, up-

wardly, under air pressure, and will remain in such position as long as air is being forced through the duct 4:. When the fan stops, the air pressure ceases and the valve 29 at once drops to its seat 31, closing the air duct 4 against backflow of hot gases, and products of combustion, from the combustio'n'chamber. In this way we prevent the waste of heat that would otherwise occur when the fan was not operating.

What we claim is I 1. In a combustion system, an oil projecting device, means for, supplying oil thereto under pressure and thereby spraying it, means for igniting the sprayed oil, means for continuously supplying air to the ignited spray to promote combustion of the oil, and automatic means for initially retarding the production of ignition relative to the supply of air.

2. In a combustion system, an oil projecting device, means for supplying oil thereto under pressure and thereby spraying it, means for igniting the sprayed oil, means for continuously supplying air to the ignited spray to promote combustion of the oil, and means for initially retarding the projection of the oil relative to the supply of the air.

3., In a combustion system, a spray nozzle, means for feeding fuel oil thereto under pressure and thereby spraying it, means for means igniting the sprayed oil, means for continuously supplying air to the ignited spray to promote combustion of the oil, and means for initially retarding the spray of the oil relative to the supply of the air.

4. In a combustion system, in combination with a spray nozzle, means for supplying fuel oil thereto under pressure and thereby spraying it, means for igniting the sprayed oil, means for continuously supplying air to the ignited spray to promote combustion of the oil, means common to said fuel and air supply for causing the same to be propelled independently and simultaneously, and automatic means for initially retarding the advent of the oil to the spray nozzle relative to the supply of air to the sprayed oil.

5. In a combustion system, a device for spraying fuel oil by pressure for burning, a pipe for supplying the oil to said device, means for forcing oil under pressure through said pipe to the spraying device, and means interposed in the length of said pipe for creating a spraying pressure on the oil before its advent into said device.

6. In a combustion system, a device for spraying fuel oil by pressure for burning, a pipe for supplying the oil to said device, for forcing oil under pressure through said pipe to the spraying device, means interposed in the length of said pipe for creating a spraying pressure on the oil before its advent into said device, and a pressure chamber communicating with said pipe between Said pressure-creating means and said oil-forcing means for increasing the time of establishing the spraying pressure on the oil.

7. In a combustion system comprising a device for spraying oil for burning, means for initially admitting oil to said device under a spraying pressure, means for supplying air to the zone of the sprayed oil, actuating means for simultaneously and independently propelling the air and oil, and means operating automatically to retard the creation of a spraying pressure of the oil until the air has been supplied to the zone of the sprayed oil.

' and oil.

9. In a combustion system, in combination with an mclosed combustion chamber, an air duct communicating therewith, means for Mamas propelling air through said duct, and means for preventing a back-flow of heatandprodnets of combustion from said combustion.

11. In a combustion system, in combination with an inclosed combustion chamber, an air duct communicating therewith through its top, means for prope ling air through said duct, and a valve in aid duct adapted to open under pressure of th e propelled air and to close in the absence of said pressure to prevent back-flow from the combustion chamber through said air duct} Q 12. A steam generating system compris ing. a combustion'chamber, a boiler inclosed therein, a fuel burning system of the type adapted to be turned on and ofi' according to generator conditions and including a burner I located said combustion chamber, and means for preventing the back flow of heat from the combustionchamber when the fuel burning system is shut off.

- 13. In a combustion system, an oil spraying, device, means for supplying oil thereto, means for igniting the sprayed ,oil, means for furnishing air to complete combustion of the oil, means for retarding the supply of one of the combustion promoting, elements.

14:- ][n a combustion system, an oil projecting device, means for supplying oil thereto under pressure and thereby spraying ,it, means for igniting the sprayed oil, means for continuously supplying air to romote combustion of the oil, and means or producing a relative retardation between the projection of the oil and the supply of the air.

- In testimony whereof, We have hereunto set our hands. v LES 1L. SCOTT.

ALLEN G. STALEY. 

